"Although the subject has received little attention, some data suggest that dental fluorosis is more prevalent among African-Americans than among other races or ethnic groups in the same community. Russell (1962), in the Grand Rapids fluoridation study, noted that fluorosis was twice as prevalent among African-American children than white children. In the Texas surveys in the 1980s, the odds ratio for African-American children having dental fluorosis, compared with Hispanic and non-Hispanic white children, was 2.3 (Butler et al., 1985b). Dental fluorosis also tended to be more severe among African-American children than white children in the Georgia study (Williams and Zwemer, 1990), although the difference was not statistically significant. In Kenya, prevalence and number of severe cases were unexpectedly high when related to fluoride concentrations in drinking water (Manji et al., 1986c), although nutritional factors could have confounded these results. The reasons for these findings are unknown and do not appear to have been explored further."

A logical theory is that because it is known that calcium mitigates the toxic effects of fluoride, any race that has high rates of lactose intolerance wherein children would ingest lower levels of milk, cheese and other dairy products, these children would have less exposure to the mineral that mitigates fluoride's toxicity.